In order to promote a thin structure, large capacity and high integration of a semiconductor device, there is currently a demand for an indispensable subsequent process for forming a multilayer wire such as a metal wire which can electrically connect each device, after forming a transistor, a bit line, a capacitor of the semiconductor device. The performance of a transistor is closely related to the speed, drive current and leakage current of the transistor, and in order to maximize the performance of the transistor, the speed and driver current of the transistor must be large and the leakage current must be small. In order to increase the speed and drive current of the transistor while reducing the leakage current of the transistor, resistance of source and drain of the transistor, resistance values of resistance of gate and contact resistance of the transistor must be small.
In order to reduce resistance values of resistance of source and drain of the transistor, resistance of gate, and contact resistance of the transistor, a self-aligned silicide (salicide) process for fabricating silicide on and/or over an interface of the drain and source and an interface of the gate is used. The salicide process is an important process in recent fabrication of a semiconductor device. Generally, silicide is advantageous in low resistance, high thermal stability, and easy application to a current silicon process, such that the silicide has been actively applied to a VLSI wire process. Furthermore, a silicide film formed on and/or over a gate electrode and a junction surface of source and drain can reduce the specific resistance of the gate electrode and contact resistance of the source and drain, respectively, thereby providing an advantage capable of greatly reducing wire resistance. As a material of the silicide, rare earth metals which react with silicon is generally used, for example, tungsten silicide (WSi2), titanium silicide (TiSi2), cobalt silicide (CoSi2) and the like. A salicide barrier film is formed on and/or over a region where salicide is not formed, using an oxide film and the like. The salicide is formed in the process sequence of forming a salicide barrier film after forming a gate, forming a photoresist pattern using a photo process, forming a salicide barrier film pattern by removing an oxide film on and/or over a region where silicide is to be formed, removing the photoresist pattern, depositing a metal film, and forming a silicide using an annealing process. However, in such a salicide process, problems arise in that the process is complicated to extend the process time and to lower yields.